Parts: model stand, clip-on lamp, and ribbon



Ribbon and clip-on lamp on door and model stand on a table



Table-top heliodon with sundial for use with sunshine




Section with critical dimensions


construction dwg

Sample construction drawing


To simulate the time of year, this single light heliodon uses a ribbon marked with the months of the year, which is attached to the edge of a door. A clip-on light is then fastened to the door according to the month to be simulated. The model stand, placed on a table, is tilted for latitude and rotated for time-of-day. When used outdoors with sunshine, a sundial governs the tilt and rotation of the model stand.



The greatest advantage of table-top heliodons is their very low cost and small size. They are accurate and valuable tools for solar design when used by people familiar with solar geometry. They can be used both indoors with electric lamps or outdoors with sunshine for greater accuracy.



Table-top heliodons are not good for learning solar geometry or the basic principles of solar responsive design, because they are not intuitive or conceptually clear. The model of a building is never horizontal and usually held at a very steep angle.